Most Recent Bulletin Report: March 2013 (BGVN 38:03)

New research data collected from submarine volcano

Richard Arculus (2012), David Butterfield (2012), and Keener and Vailea (2012) discussed the Submarine Ring of Fire Expedition 2012 of the research vessel RV Revelle during 14-15 September 2012. They conducted bathymetric profiles and submersible observations of a caldera originally called 'Volcano O' in the Tonga arc (figure NIU1). During this cruise, the name 'Niua Tahi' was given to this extraordinarily symmetrical, circular caldera, 15 km in diameter at 1.2 to 2 km depth, by a Senior Geological Assistant aboard from the Tonga Ministry of Lands, Environment, Climate Change and Natural Resources. According to Keener and Vailea (2012), "Volcano O, was named 'Niua Tahi' during our expedition by the Ministry, which in Tongan means 'sea', with the small cone within it being named 'Motu Tahi', or 'island in the sea'."

Figure 1. Map of operations of Submarine Ring of Fire 2012 in the NE Lau Basin. Map features the NE Lau Basin area, where the majority of cruise took place. The inset in the upper left shows a key to the various tasks for the entire cruise, and the insert map in the lower right shows the general area with respect to the locations of Samoa and Fiji. Niua Tahi volcano is identified as 'Q324: Motutahi' (the new name for the volcano's small cone) on the map. Image from Resing and Embley (2012); courtesy of Submarine Ring of Fire 2012: NE Lau Basin, NOAA OER.

Niua Tahi is a giant, near circular caldera ~15 km in diameter, with a floor at a depth of about 2 km (Arculus, 2012). A young cone (Motu Tahi) in the SE sector rises 730 m above the floor to a summit at a depth of 1,270 m depth. The volcano is in the rear arc of the Tonga system, located ~40 km W of the chain of subaerial submarine volcanic edifices that define the volcanic front of the Tonga Arc, and 25 km E of the spreading ridge of the Northeast Lau Spreading Center. The composition of the cone and surrounding floor is predominantly dacite. Towing with sea floor cameras over the cone and various parts of the caldera resulted in the discovery of at least three sources of hydrothermal particle venting on the cone's summit and adjacent to the inner caldera walls.

During the cruise, the remotely operated vehicle (ROV) Quest 4000 (operated by MARUM, the Center for Marine Environmental Sciences at the University of Breman, Germany) traversed from W to E over the volcano summit and around the margins of the central cone. The cone contained a shallow pit surrounding what appears to be a volcanic vent, probably the site of the most recent volcanism (figure NIU2). The ROV showed that the summit of the cone was mantled with a ubiquitous sulfur rich layer that coated rugged blocks of pillow lava, lava tubes, and ash-and-blocks deposits.

Figure 2. (a) Multibeam bathymetry image of Niua Tahi, looking N, with two-fold vertical exaggeration. Color scale for depths is shown in upper right. (b) Multibeam bathymetry image of the cone in the caldera of Niua Tahi. The image is viewed looking E, without vertical exaggeration. The color scale for depths from Figure NIU2a is the same for this figure. Both images courtesy of Susan Merle, Oregon State University, Submarine Ring of Fire 2012 Exploration, NOAA Vents Program; on web site of Arculus (2012).

The ROV images revealed the presence of a NE-trending elongated pit crater at the cone's summit emitting a plume bearing a sulfurous particulate rich plume. Several previous observations of the water column detected similar plumes. Hot, clear water (~105°C) welled up in numerous places through the loosely agglomerated pyroclastic materials forming both the rim of the crater and flanks of the cone. The attempt to descend the ROV into the pit for a closer look was thwarted by the dense clouds of sulfurous 'smoke.'

The most recent volcanic activity was likely dominated by lava and volcaniclastic debris.

Bulletin Reports

All information contained in these reports is preliminary and subject to change.

Richard Arculus (2012), David Butterfield (2012), and Keener and Vailea (2012) discussed the Submarine Ring of Fire Expedition 2012 of the research vessel RV Revelle during 14-15 September 2012. They conducted bathymetric profiles and submersible observations of a caldera originally called 'Volcano O' in the Tonga arc (figure NIU1). During this cruise, the name 'Niua Tahi' was given to this extraordinarily symmetrical, circular caldera, 15 km in diameter at 1.2 to 2 km depth, by a Senior Geological Assistant aboard from the Tonga Ministry of Lands, Environment, Climate Change and Natural Resources. According to Keener and Vailea (2012), "Volcano O, was named 'Niua Tahi' during our expedition by the Ministry, which in Tongan means 'sea', with the small cone within it being named 'Motu Tahi', or 'island in the sea'."

Figure 1. Map of operations of Submarine Ring of Fire 2012 in the NE Lau Basin. Map features the NE Lau Basin area, where the majority of cruise took place. The inset in the upper left shows a key to the various tasks for the entire cruise, and the insert map in the lower right shows the general area with respect to the locations of Samoa and Fiji. Niua Tahi volcano is identified as 'Q324: Motutahi' (the new name for the volcano's small cone) on the map. Image from Resing and Embley (2012); courtesy of Submarine Ring of Fire 2012: NE Lau Basin, NOAA OER.

Niua Tahi is a giant, near circular caldera ~15 km in diameter, with a floor at a depth of about 2 km (Arculus, 2012). A young cone (Motu Tahi) in the SE sector rises 730 m above the floor to a summit at a depth of 1,270 m depth. The volcano is in the rear arc of the Tonga system, located ~40 km W of the chain of subaerial submarine volcanic edifices that define the volcanic front of the Tonga Arc, and 25 km E of the spreading ridge of the Northeast Lau Spreading Center. The composition of the cone and surrounding floor is predominantly dacite. Towing with sea floor cameras over the cone and various parts of the caldera resulted in the discovery of at least three sources of hydrothermal particle venting on the cone's summit and adjacent to the inner caldera walls.

During the cruise, the remotely operated vehicle (ROV) Quest 4000 (operated by MARUM, the Center for Marine Environmental Sciences at the University of Breman, Germany) traversed from W to E over the volcano summit and around the margins of the central cone. The cone contained a shallow pit surrounding what appears to be a volcanic vent, probably the site of the most recent volcanism (figure NIU2). The ROV showed that the summit of the cone was mantled with a ubiquitous sulfur rich layer that coated rugged blocks of pillow lava, lava tubes, and ash-and-blocks deposits.

Figure 2. (a) Multibeam bathymetry image of Niua Tahi, looking N, with two-fold vertical exaggeration. Color scale for depths is shown in upper right. (b) Multibeam bathymetry image of the cone in the caldera of Niua Tahi. The image is viewed looking E, without vertical exaggeration. The color scale for depths from Figure NIU2a is the same for this figure. Both images courtesy of Susan Merle, Oregon State University, Submarine Ring of Fire 2012 Exploration, NOAA Vents Program; on web site of Arculus (2012).

The ROV images revealed the presence of a NE-trending elongated pit crater at the cone's summit emitting a plume bearing a sulfurous particulate rich plume. Several previous observations of the water column detected similar plumes. Hot, clear water (~105°C) welled up in numerous places through the loosely agglomerated pyroclastic materials forming both the rim of the crater and flanks of the cone. The attempt to descend the ROV into the pit for a closer look was thwarted by the dense clouds of sulfurous 'smoke.'

The most recent volcanic activity was likely dominated by lava and volcaniclastic debris.

The relatively unknown 861-m-high Morne aux Diables (Devils' Peak) stratovolcano forms the northern tip of the island of Dominica. Several nested craters and a 90-m-high, 335-m-wide lava dome are located within a larger 1.2-km-wide crater. The complex overall includes seven andesitic lava domes with a central depression where a cold soufriere is located. A chain of lava domes, two of which form a peninsula on the SW flank, form an E-W belt across the southern flank of the volcano. Bathymetry shows a double-peaked lava dome (known informally as Twin Peaks) off the northern coast, which is truncated by a 4-km-long fault-bounded cliff. No eruptions are known from Morne aux Diables in historical time, although the volcano has a youthful appearance and activity at flank domes likely continued into the late-Pleistocene and Holocene. The youngest (NW) summit crater contains an active thermal area with bubbling springs. Severe earthquake swarms in 1841 and 1893 were associated with either Morne aux Diables or Morne Diablotins to the south. Shallow volcano-tectonic seismicity was detected as recently as February 2010.

This compilation of synonyms and subsidiary features may not be comprehensive. Features are organized into four major categories: Cones, Craters, Domes, and Thermal Features. Synonyms of features appear indented below the primary name. In some cases additional feature type, elevation, or location details are provided.

Domes

Feature Name

Feature Type

Elevation

Latitude

Longitude

Bellevue Mountain

Dome

670 m

15° 37' 0" N

61° 27' 0" W

Brulés, Morne

Dome

15° 35' 0" N

61° 27' 0" W

Destinée, Morne

Dome

15° 35' 0" N

61° 26' 0" W

East Cabrit

Dome

140 m

15° 35' 0" N

61° 29' 0" W

Twin Peaks

Dome

-153 m

15° 40' 15" N

61° 28' 35" W

West Cabrit

Dome

170 m

15° 35' 0" N

61° 29' 0" W

Thermal

Feature Name

Feature Type

Elevation

Latitude

Longitude

Penville Cold Soufrière

Fumarole

Morne aux Diables stratovolcano at the northern tip of the island of Dominica rises above beaches on the NE shore of the island near the village of Calibishie. Several nested craters and a 90-m-high, 335-m-wide lava dome are located within a larger 1.2-km-wide crater. The youngest, NW crater contains an active fumarolic area. No eruptions are known in historical time. Severe earthquake swarms in 1841 and 1893 were associated with either Morne aux Daibles or Morne Diablotins to the south.

Photo by Jan Lindsay, 2000 (Seismic Research Unit, University of West Indies)

The NW side of Morne aux Diables volcano at the northern tip of Dominica is seen from the hydrofoil ferry between Guadeloupe and Dominica. Lava domes are prominent on the 681-m-high volcano, both at the summit and its flanks. Bathymetry reveals evidence for a twin-peaked lava dome about 5 km off the NW coast that reaches to within 153 m of the sea surface. Both domes, known informally as Twin Peaks, rise more than 1000 m above the sea floor.

Photo by Paul Kimberly, 2002 (Smithsonian Institution).

Morne aux Diables volcano rises above the Atlantic coast of NW Dominica. The summit of the volcano is formed by a complex of lava domes, and flank domes, which extend in a roughly E-W chain across the southern flank of the volcano, are visible on the left horizon.

Photo by Paul Kimberly, 2002 (Smithsonian Institution).

Morne aux Diables volcano at the northern tip of Dominica is a stratovolcano composed of andesitic lava domes, lava flows, and block-and-ash flow deposits well exposed in coastal sea cliffs. Volcanism at the dominantly Pleistocene Morne aux Diables is considered to have likely continued into the Holocene; unconsolidated block-and-ash flow deposits extend to the NW and NE coasts. Fumarolic areas are present on the volcano, and the Penville Cold Soufrière, an area of bubbling pools, lies within the youngest crater of the volcano.

Photo by Lee Siebert, 2002 (Smithsonian Institution).

The following references have all been used during the compilation of data for this volcano, it is not a comprehensive bibliography. Discussion of another volcano or eruption (sometimes far from the one that is the subject of the manuscript) may produce a citation that is not at all apparent from the title.

WOVOdat is a database of volcanic unrest; instrumentally and visually recorded changes in seismicity, ground deformation, gas emission, and other parameters from their normal baselines. It is sponsored by the World Organization of Volcano Observatories (WOVO) and presently hosted at the Earth Observatory of Singapore.

EarthChem develops and maintains databases, software, and services that support the preservation, discovery, access and analysis of geochemical data, and facilitate their integration with the broad array of other available earth science parameters. EarthChem is operated by a joint team of disciplinary scientists, data scientists, data managers and information technology developers who are part of the NSF-funded data facility Integrated Earth Data Applications (IEDA). IEDA is a collaborative effort of EarthChem and the Marine Geoscience Data System (MGDS).